Sean O'Brien, Jared Payne and Jonathan Sexton are injury concerns for Ireland ahead of the Six Nations game against Wales in Cardiff on 14 March.
Flanker O'Brien and centre Payne suffered concussion in Sunday's 19-9 victory over England, which keeps the Irish on course for the Grand Slam.
The pair have started the graded return to play protocols for concussion with no date set for their return.
Fly-half Sexton sustained a 'minor' hamstring injury against England.
Sexton scored 14 points at the Aviva Stadium before being forced off with the injury midway through the second half.
O'Brien, who has just returned after missing much of the last 18 months, was also substituted after a heavy hit in the first half.
Payne made way for Felix Jones with nine minutes remaining in the game.
Ireland top the Six Nations standings after three games, two points clear of England and Wales.